For property managers, synagogues, yeshivas, hospitals, and building operators serving observant communities, one question comes up again and again. “How do you provide secure, code-compliant door access without asking anyone to violate Shabbat?” DeltrexUSA built the answer — and it’s the only Rabbi-Approved Shabbat Access Control System manufactured in the United States.
What makes it halachically compliant?
Our Shabbat Gramma System (SGS) uses a principle called gramma, or indirect action. Rather than directly opening or closing an electrical circuit — which is prohibited on Shabbat — the system relies on a technique called “modified current.” A touch-sensitive switch detects a change in current, voltage, or frequency caused by human contact, and a separate, pre-existing electronic cycle (a short pulse repeating every few seconds) is what actually triggers the door to unlock. Because the person touching the switch never directly initiates the unlocking action, and because the response happens on a delay tied to an independent, pre-set cycle, the action falls under the halachic principle of gramma rather than direct melakha (prohibited labor).
This isn’t a workaround we invented ourselves. The Shabbat Gramma System has been reviewed and approved by prominent rabbis, and a certificate of compliance is available on request — which matters enormously to institutions that need to document their compliance, not just assert it.
Why this matters for distributors and installers
If you sell into any market with a meaningful observant Jewish population — apartment buildings, senior living, hospitals, synagogues, yeshivas — you already know this request comes up. Most access control manufacturers simply don’t have an answer, which means the sale either dies or gets referred elsewhere. Carrying a Rabbi-approved system that’s made in the USA (with all the lead-time and support advantages that come with domestic manufacturing) turns a request you’d otherwise lose into a sale you can close and support yourself.
Real-world applications
Our #770 Shabbat System is built for a single door or gate with two keys/switches, and it’s compatible with magnetic locks, electric locks, and electric strikes — meaning it can typically be integrated into a building’s existing access control hardware rather than requiring a full rip-and-replace. That makes it a practical upsell or line-item add for jobs you’re already quoting.
The bottom line
There’s real depth behind this system. The halachic reasoning traces back to a Mishna about indirect firefighting on Shabbat. It’s been written about by rabbis across multiple generations of religious-legal scholarship. But for a distributor or installer, the practical takeaway is simpler. This is a product category with almost no competition. There’s real demand in specific but consistent markets, and a manufacturer (us) that can back it with documentation and support.
If you serve buildings or institutions where this question comes up, let’s talk about adding it to your offering. Call 718-401-4006 or visit deltrexusa.com/shabbat for full specifications.
